Experiences

Chemical inorganic nomenclature

Laura Capella

Italy

Vocational School

Chemistry

Teaching in class

Chemical nomenclature of inorganic compounds is a difficult obstacle to overcome during the High School first two years, in every kind of school, scientific or not (in Italy there are many different kinds of it).
The matter is of capital importance, not to say it could be bypassed.
In spite of this importance, you cannot dedicate a never-ending period of time, and often you reach it in the final part of the second year when students are about to be tired of a long period of study efforts. Sometimes I decided to dedicate a very long time to work with this topic, anyway they did not seem to learn it better than usual, and, moreover I had less time to make other important subjects. I tried other ways as introducing it in other periods of the year, and even contemporary to other matters like chemical reaction stoichiometry, just to make it more interesting or clearly useful to the comprehension of more interesting things, always without remarkably better results. The fundamental thing is that students don't want to learn a boring matter for which they don't see the utility.
So I decided to try a Cooperative Learning approach with this difficult matter.
Procedure:
I divided the class in groups of four students and assigned to them several nomenclature exercises to cope with. Exercises were of the following types: Formula to name and name to formula. I had already explained in a brief preliminar lesson, how to recognise and how to assign Oxidation Numbers for each Element present in a formula and another brief one about classification of binary compounds and the IUPAC's rules for naming them. Then I had given few precise instructions to make them know how to deal with the nomenclature work. (Afterwards I repeated it all with ternary compounds).

To make the procedure automatic you have to do quite a lot exercises, usually students don't do that unless they are compelled to. In this way everybody has to do the work and to pay attention, and they even have fun in doing that. Good work was done even in groups with no above average students.
The really important thing is to assign a precise job to everybody: for example a member of the group has to pay attention to the oxidize number of elements, while another member has to remember and assign compound class name and/or the precise name of the compound analysed. The most important job to assign is that somebody has to keep the attention on and to remember the others to be quiet and another key task is to stay on clock, to make sure there will be results in the assigned time.
The way in which the group has been able to work could be marked for real life competences, while afterwards a test should be done for chemical subject competences.
The test examination was quite good for everyone, because the procedure was thoroughly understood by everyone during the group work.